The trans-decalin lactone (35) has been elaborated in five steps from the bromo-acetal (10) using a novel stereoselective intramolecular radical mediated cyclisation reaction, viz (10)→(12) in tandem with an intramolecular Mukaiyama aldolisation, viz (34)→(35). Treatment of (35) with methanolic potassium hydroxide next led to the βγ-unsaturated lactone (37), which on oxidation with pyridinium dichromate t-butylhydroperoxide complex ...
